Several hours earlier:
1. It's important to have a healthy, substantial breakfast, of course, but it's just as important to eat well the night before so that you feel your best in the morning. Choose nutritious foods that fill and satisfy, and remember to limit caffeine to one or two servings. Chances are you'll already be feeling jittery, so put a cap on your coffee consumption.
2. Check the hourly forecast and grab any extra items that you may need: an umbrella, a raincoat, gloves, or suitable footwear, for instance.
3. Shoes are important: make sure your pair is both weather-appropriate and easy to walk in, because the last thing you want to do is trip your way through the office. The night before your interview, wear the selected shoes with socks for a couple hours to guarantee that they're broken in and comfortable.